How Disney's Happily Ever After Works

I've done episodes about different aspects of the Disney parks, and earlier in ten I had planned on going to Disney World and uh in twenty seventeen, Disney World over at the Magic Kingdom started a brand new fireworks display called Happily ever After. And after I heard about it and heard what was going to be part of Happily ever After, which would include three D projection mapping, I'll talk about that this episode. I realized that this was

a really cool idea. I could use that as a specific example and take the opportunity to talk about the technologies that make that show possible. So, in the interest of full disclosure, I want to let you guys know I reached out to Disney and told them what I wanted to do and asked if they might be able to set up an interview with one of their imagineers who was responsible for working on this this project. So I did that and I heard back from Disney. They

were very, very gracious. They informed me that they did not have any opportunities for any interviews during the time when I was going to be at Disney anyway. I told them this, you know, the span of the week where I would actually be at the park. However, they did give me a one day park hopper pass so

that I could go I which I used. So I just wanted to make that full disclosure because while there was no agreement about doing a show or having access to anything, it was literally they said, thank you for your interest. Here's a day at the park. I just want to let you guys know that that had happened, because you know, I want to be on the up and up. But I had planned on doing the show anyway. So yeah, alright, So what that's what is happily ever After? Well,

it is the successor of a show that was called Wishes. Uh. This is the big nighttime show at the Magic Kingdom. Wishes was primarily a pyrotechnics show, a fireworks display and I was kind of sad to see Wishes go. Wishes had been around for I think thirteen years at the Magic Kingdom Park and then uh they decided to swap it out. I had a personal connection to Wishes because Wishes was hosted and I use air quotes for hosted by jim NYE. Cricket. The voice of Jiminy Cricket was

one of the narrators for the show Wishes. And I don't want to ruin the magic for anybody, but Jiminy Cricket used to be voiced by an actor named Eddie Carroll, and Eddie Carroll was a friend of the family. He passed away a few years ago, but Eddie Carroll's a friend of the Strickland family, and so it was kind of sad to see that show go because that was another connection to someone I had known and had had

hung out with. Very nice man. Uh So I was sad to see that go, but I was also excited because I I don't think anything at Disney should be considered as a as a forever and ever permanent kind of installment, because then you don't ever have the opportunity to experiment and innovate. And I think that Walt Disney was very much concerned with the concept of innovation, so I am glad that they had the chance to make this new show. Fireworks in Disney date back a long way.

The first fireworks display at a Disney park was at Disneyland in nineteen fifty eight. It was called Fantasy in the Sky. As I said, Wishes was the most recent fireworks display over at the Magic Kingdom until earlier in sev It was kind of cool. It had five hundred fifty seven firing queues that meant at five fifty seven different points during the show they would fire off at least one, if not multiple fireworks. H and so it was neat to see that show. I hope you had

a chance to see it. If you've ever been to the Magic Kingdom, I hope you had a chance to see Wishes. It was pretty good, but happily ever after. Has a lot of new technologies involved in it, not just fireworks, not just spotlights, not just lasers, but also three D projection mapping, which has been used a couple

of times in Disney's past, including a notable one. The first noted use of three D projection mapping was at a Disney Park, but this was the first truly major use of it in a big Disney show that was meant to be a kind of a nightly performance. And there's a lot of different breakdowns online you can find for the show that kind of explain the flow of it. One of them is on w d W Magic. It's

called Deconstructing Happily. Ever, after it breaks it down like this, it says that there are seven sections to the show, and the first one is called Desiring the Dream. This is their terminology. It's not necessarily the internal one, but Desiring the Dream, which sets the scene and features the first instances of projection mapping. I'll explain what that means

a little bit later in this episode. The second section is called Boldly Beginning the Journey, and that one has some various laser effects along with projection mapping and some fireworks. Then you have friends on the Journey. Section four is Love is the Journey. Section five is Overcoming Adversity, which includes both projected and real fireworks, which is kind of cool.

They'll have a projected firework on the castle itself and then it will transition to a real firework in actual space, so you watch as a pretend firework is fired off on the scene of the castle and a real one takes off right at the same point, so that you can then have that perfect transition. It's a really neat effect. Section six is the Heroes Happily ever After, and the

final section is find your Own Happily ever After. Meanwhile, the Disney Wiki has a slightly different naming system for these that goes with Happily ever After, wish Adventure, Friendship, Love Adversity, Heroes fight Back, Peace Restored, and Happily ever After referees. Each section has various effects, characters, music, and dialogue associated with it. So let's talk about how how all this works. I mean, it's when you experience it

as a show. You're hearing music, you're hearing dialogue, You're seeing the imagery projected directly onto the castle, Cinderella's castle at the Magic Kingdom. You're seeing the fireworks, you're seeing the spotlights, you're seeing the lasers. How do you coordinate all of that? The answer, by the way, spoiler alert, is computers. Yeah, that's pretty much what you have to use. But obviously there's a lot of different individual components here.

So let's start with fireworks. So we actually did a pair of episodes about fireworks, uh a few years back back in tween. This would be when Lauren vogeo Baum was my co host, and Lauren and I did these two episodes about fireworks. They are titled tech Stuff Lights Some Fireworks. That one published on July twenty fourteen, and the second part was called Fireworks Part two because apparently

we ran out of creative ways of naming episodes. That one published on jen But I'm gonna go over some of the salient facts so that we understand what's happening, because I don't need to go in as much detailed since we already have episodes. But it's been a few years, so let's catch everybody up. First of all, what is a firework? Well, it's an explosive or combustible device designed to create an impressive light display and or loud noise.

These days, the most common basic ingredient and fireworks is called black powder, which is similar to gunpowder. It's made from sulfur, charcoal, and potassium nitrate, also known as saltpeter. So those are your three basic ingredients for gunpowder. If you remember from The Wonderful musical seventy. That's what Adams was asking of his wife Abigail to send them saltpeter

because they needed it for their guns. Legend states that fireworks were created by accident when a chef in China was mixing together sulfur, saltpeter, and charcoal in a kitchen and discovered that if you compressed it and then lit it on fire, it would ignite with explosive force. There's no word whether the chefs survived this discovery, or if perhaps noodles found their way to the moon. No one really knows, and in fact, this is probably an apocryphal story,

but it is a popular one. Another potentially apocryphal story traces the origin of fireworks back to a specific monk named Le Sian who lived in China about one thousand years ago. But there's so many different sources that use the exact same phrasing to describe the story that to me, it sounds like they're all working from a a single primary source, or they're perpetuating a whole lot of copying

and pasting. At any rate, it sounds like there's a lot of plagiarism is a strong word, let's just say very creative writing going on here, and I can't find anything that actually confirms or denies that legend. It may very well have an element of truth to it, or it could be completely baseless, and it's just one of those things that's been passed around by multiple people. Scholarly sources, however, point to the development of gunpowder originating sometime around the

eleventh century Common Era in China. Other people worked on it as well over the following centuries. Roger Bacon discovered in the thirteenth century that black powder burned with a quick flash if you lit it. So if you just had black powder loose and you lit it, it would go flash and just be gone. But if you were to compress it by packing it into a container and then you lit it, it would explode and go boom. And that's because you have the basic needs for fire

in very high concentration in a small area. Uh. That means that means you've got fuel. Fuel in this case is the in the form of charcoal and sulfur, and you have oxidizer that would be the potassium nitrate. Oxidizer are the thing that allows fuel to burn. The one we're really familiar with is oxygen, thus the name you may remember the triangle that's required to have fire. You need fuel, heat, and oxygen. Technically, you don't really need oxygen.

You need an oxidizer. Oxygen just happens to be one of the oxidizers. It's the most plentiful one around us on normal day to day basis. Pretty much when it's not around us, we tend to not enjoy ourselves so much, so we're really familiar with that one. Modern fireworks tend to use other stuff as oxidizers. Uh Like you know, potassium nitrate was very popular for a while, but it's not used as much these days. It's not as environmentally

friendly as some other oxidizers. It creates byproducts that could potentially be harmful to say, surrounding wildlife or people, So potassium nitrate is not used as frequently in modern fireworks. We're seeing more stuff like sodium and potassium pair your date being used instead or pariah date, I guess is the best way of saying it. Pariah date, not perio date. Don't write to me, I know and messed it up. The colors created from fireworks are dependent upon the materials

that you place inside those fireworks. Because different stuff burns with different color flames. We've learned this over centuries where people have worked with various materials, they've caught on fire and we've looked at the flames and said, oh, that's pretty. So if you want to have different effects with your fireworks, you would add different types of metallic salts, that kind of thing to your mixture in order to create the sparking effect that you want. So here's a quick guide

to some of your basic colors. If you wanted red fireworks, you would generate that by burning strontium salts, lithium salts, lithium carbonate, strontium carbonate, which would give you a very bright red. Strontium carbonate would So those are your reds. If you wanted to create orange, you would use calcium salts or calcium chloride. If you wanted yellow, you'd use sodium salts like sodium chloride. If you wanted green, you would go with barium compounds and a chlorine producer, so

barium chloride. If you want blue, you would go with copper compounds and a chlorine producer, so copper chloride. You want purple, then you would want to mix blue and red together. It's kind of like grade school. And that meant that you would mix together strawntium and copper. Typically, if you wanted silver effects, you would use something like aluminum, titanium or magnesium in there to get the explosive patterns. Because that all that does is just give you color.

It doesn't automatically make the fireworks spread out in a particular shape. If you want a specific shape, you would have to pour them these metallic salts into lumps made of clay or a kind of Doughey material. These would end up being pocket of that material, and they're about three or four centimeters across, and in the industry they refer to these things as stars. So each one's three

or four centimeters across. You might have a whole bunch in a single firework, but each one of these would represent a blast of color like one of those big sparks you see in fireworks. So you're talking about lots

and lots of them in the really big ones. And uh, the way you place them inside the firework determines where they're going to go, just based upon where the blast is right, You've got a essentially a black powder core that's going to force everything into different directions, and you place the stars around the core in the particular uh, the particular arrangement you want in order to create the effect you're going for. It's pretty cool that you can

do this, you know, manually, if you wanted to. In fact, there are a lot of places that still do this manually because frankly, you're you're working with stuff that's pretty dangerous, so you want to be really careful with it. You can't, you know, you can't treat black powder casually or you're gonna have an explosion on your hands. Now, typical firework rocket will have several stars packed into it, and like I said, they had to be placed meticulously in the

rocket to get that desired effect. And then they use a time delay fuse that would lead to the burst chamber of black powder, which the stars are centered around. So you typically have two different kinds of fuses in your firework. You have a quick burning fuse that will go to the uh the launch blast of black powder. You can think of a firework is having two chambers, the first one being the launch chamber. That's what's going to provide the force necessary to propel the firework into

the air. Disney is a little different, but we'll talk about that in a second. So your typical firework, you would have that first black powder bunch that shoots the firework into the air. The fuse would then lead to a more slow burning fuse, And by slow we're talking about degrees here. It's not like it's super slow, but it would burn slower so that the secondary charge, the burst charge, will explode at a precise timing, typically when you want to get to the the top of the

arc of the fireworks flight. So you time this out by measuring out how much black powder you're using. This is all based upon also the weight of the firework. When it's all finished, like, you have to do a

lot of math. You have to figure out how heavy is the firework, how much force is the blast powder going to create when it's doing this lift, how fast will it get to the top of its flight path, and how long does the slow burning fuse have to be in order for the burst black powder to ignite at the proper time to ignite all those stars and send them out in the various directions. There's a lot

of math involved often that that's just for one firework. Also, you've got to remember, based upon the way you design the firework, you're gonna get very different effects. Obviously, if you've seen any fireworks displays, you've probably seen somewhere it's just a very bright star flying through the sky, or another one where it's a really cool kind of uh cascade effect. All of these are based upon the way that you've actually packed the powder and the stars together,

so really precise. And it's fascinating to me that we ever figured this stuff out because I look at it and I think it's so pretty how much trial and error was necessary to understand exactly how to do this correctly? Would I have had the patients to do it, or would I be known as Johnny the three fingered idiot who probably worked a little too closely with black powder. I think we all know the answer to that, so you don't need to write me and tell me. I

know what the answer is. So let's just be thankful that people who are smarter than I am were the ones who developed fireworks. Now, more advanced fireworks may have multiple burst chambers, so not just the one, they might have multiple ones so that you get extra effects from

the same firework. You don't have to fire multiple ones to get it, and you might have different break charges in between these different chambers, so that you can have them ignite at different points of the flight, and therefore you get very different effects as a result. The shape of the firework bursts is determined by the arrangement of the stars inside the projectile and whether or not it

is a multi break firework. The shape of the shells also determines the shape of the explosion, and here is a collection of your basic types of fireworks. Shells. You've got palm which contains large comets or charges in the shape of a solid cylinder that travel outward, explode and then curved downward like the limbs of a palm tree. You have round shells. These explode and spherical shape, usually of colored stars, so very typical firework that you would see.

A ring shell explodes to produce a symmetrical ring of stars. Another very typical firework willow. This contains stars. High charcoal composition makes them burn longer that fall into the shape of willow branches and may even stay visible until they hit the ground. So this is that cascading effect I was talking about a second ago. Round dell shells. These burst into a circle of maroon shells that explode in sequence.

Chrysanthemum shells. These burst into a spherical pattern of stars that leave a visible trail with an effect somewhat suggestive of the flower pistol shells like a chrysanthemum shell, but has a core that is a different color from the outer stars. So you get a contrast maroon shell which makes allowed bang and serpentine bursts to send small tubes of incendiaries skittering outward in random paths, which may culminate in exploding stars. Obviously, these are all basic types of fireworks.

There are others, and there are combinations of these as well. Like I said, fireworks have the two chambers, you've got the different fuses that will allow those different chambers to ignite at different points of the flight. To me, it's a very low tech but elegant solution to making an explosion happen exactly when you want it to and to

get the effect that you're hoping for. And typically you would launch fireworks, these big ones anyway, from mortars and a mortar firework mortar typically it's just a tube that has one end sealed off, so the base of the firework goes down against the bottom of the tube, you light it, use the tube to aim the firework at the right angle, flies out the end, and shoots off preferably exactly where you want it to, and then it

blows up. Pretty simple design. Some mortars have sparkers at the base of them, and those are hooked up to a control board which could also be hooked up to a computer program, so the computer program can send a command that will send a electric current down the wire, sparking the sparker, which then ignites the fuse for the firework and fires it off. If you have a computer program that has everything coordinated in it, then you just

run the program. As long as all the fireworks are set up ahead of time, then it should work pretty well and you will have your fireworks going off at the appropriate time. If you wanted to actually time this out properly, then you kind of have to work backwards. You have to figure out what point in the show you want something to happen, and you mark down the time stamp. So you start the show, you have a moment in the show and you say this is when I want the firework to go off. You mark the

time stamp down and you start working backwards. So you take the firework that you're planning on firing and you say, all right, well I need it to explode at this point, So that's the explosion point. How long does it take for the quick fuse to burn to the or the slow fuse to burn to the burst chamber? How long

does that take? Based upon that, we know know how long back how far back we need to go for the birst chamber to light Based on that, you can say, all right, well, how far does the lift chamber need to uh? When does that need to light up in order for the burst chamber to be in the right

position at the right time. So you just keep working backward, and as you do that, you start to finally get to the point where you say, this is the moment in the show where I have to launch so that at this later moment I get the effect I want. And as long as you're being very consistent with the way you're producing your fireworks, you should get the same effect more or less every show. There might be small changes based on weather and some other things that are

kind of outside your control. There're gonna be some small change differences in quality, for example, with fireworks. But for the most part, you're gonna be pretty consistent because physics is like that. If physics were not like that, we wouldn't have physics, because you have to have the world makes sense in order for us to be able to talk about rules. If the world didn't make sense, then

fireworks would be even more dangerous than they already are. Disney, as I mentioned, it is slightly different from this typical mortar approach. They don't they don't use mortars with sparkers. They typically use mortars that have air compressor guns in them, so they can actually use compressed air to fire a

firework into the sky. Now, what that means is that their fireworks don't require this lift chamber of black powder because the lift is created from the burst of compressed air behind the firework, So they can actually cut down on the amount of black powder they need to use for each rocket that's in their show. That also means that they cut down on the amount of smoke they generate per fireworks show because they're not burning as much black powder. So there is a practical, uh side effect

to this. Besides the fact that you know they can use compressed air to to get fireworks into motion and into into the right place before they explode. Now I've got a lot more to talk about with the various technologies that are used and happily ever after. But before I get into that, let's take a quick break to thank our sponsor. All Right, so we've covered fireworks, but there are other elements too happily ever after that we need to talk about, and another one would be laser lights.

We covered lasers in an even more recent episode of tech Stuff than we did fireworks. That episode was Pew Pew Lasers, which published on June four, so super recent. I'm not gonna go into any real big detail with lasers because of that, but I'm gonna give you a little bit of an overview just in case you for gotten, and that way you don't have to necessarily go and dig up that old episode to really get a full appreciation of the technology that is making the show happen.

Laser used to just be an acronym, right, but now it is a a noun all on its own. We're so proud of this word that it's now achieved true noun status. The acronym stands for light amplification by stimulated emission of radiation, which sounds naughty, but it's not. It just means that you're using energy to stimulate the electrons that are in orbit around certain atom nuclei, which when you put it that way, doesn't sound nearly as exciting.

Lasers are monochromatic, which means they produce one wavelength of light and thus one specific color because the wavelength of light it directly corresponds to the color of light. This is true both in the visible spectrum and outside of it, but obviously outside of the visible spectrum, it really isn't

something we can perceive. You can have infrared lasers, but you wouldn't be able to see them, But anything that's in the visible spectrum, obviously the wavelength would have to be a specific length in order for us to perceive it. Um that type of light really depends upon the amount of energy that the electrons are releasing during the lazing process. That in turn is dependent upon the material you're using

in order to have your lasing medium. So you choose your lasing medium that will do that will determine exactly how much energy you have to pour into the medium

to excite the electrons. When the electrons emit that excess energy when they want to return to their ground state, which I'll talk about in just a second, that will end up taking the form of photons, and the photons will be of the wavelength the actual light will be of the wavelength that is dependent upon uh that lasing medium, right, So it all comes down to your choice of materials.

That tells you how much power you have to put into it in order to stimulate the electrons, and thus what color of light you're going to get out of it. At the end of it, all the light waves that come out of a laser are in phase with one another. That means they all crest and descend in their wave patterns the same way, which also means you can pack

a whole bunch of light waves together really tightly. Think about like putting together some curved pieces of track from a railroad set, and you have a whole bunch of curves that are the same grade, so they're all of the of the same same gentle curve to the right, let's say, and you've got a stack of them, Well, they stack together really nicely because they all take the same shape. This is the same idea, but because you have all of these light waves in phase with one another.

You can pack them together very tightly, they don't jumble up, and that's how you get coherence. That's how you get a coherent laser. That's what we call that. To get a little more granular, atoms have electrons that orbit the nuclei of the atom. That's of course the protons and or well protons and possibly neutrons. You gotta have a proton there, but you may or may not have a

neutron there, depending upon the actual atom in question. The electrons orbit these nuclei at a particular distance or really a particular potential range from the nuclei. We tend to draw it in very simplistic terms. The reality is a

bit more messy. But we talk about electron shells, these energy shells that electrons will inhabit, and each energy shell has a certain number of vacancies available, and electrons will take on the vacancy that is closest to the nuclei, and then other electrons will take the next closest once an entire shell fills up. Well, if you pour energy into an atom, that energy will then transfer over to the electrons and the ones that are on the outermost shell can be excited so that they jump out even

further away from the nucleus. Once that energy that you're using to energize the electrons goes away, the electrons will try and return to their ground state, that outer electron shell that they normally would be in if they had not just been boosted further out. As they do, so they have to give up that excess energy they've picked up. Otherwise they're just too they're just too darn Swoll for that energy shell, and you can't have a Swoll electron there,

so they have to give up that energy. They do that in the form of photons. So again the type of material you're using determines how much energy you're poor ng in, and that in turn determines the type of photon the wavelength of light that will be emitted when the electron comes back down to its ground state. Uh So that that kind of gives you the overview of how lasers work in a very general sense. There's also

obviously a lot of other elements. You have to have a power source, you have to have a lens of some sort. Typically there's some interesting mirrors there. The lazing system tends to involve a chamber that has UH mirrors on either end of the chamber, one of which is only partially silvered, so that you can have the lasers continuously stimulate the lasing medium and thus emit more laser light until it can escape out of the partially silvered

part of the chamber. It's pretty cool, Like you start looking into it and you realize, yeah, I understand why James Bond villains really considered the laser a go to doomsday device, because these are pretty interesting things here. The lasing medium itself kind of acts as an amplifier for laser lights, so again a very important component for your laser, and two different things, two different factors really determine how

well laser light shows up at any given time. Those two things would be the wavelength of the light itself, so where in the spectrum does it fall, and how much power was put into the laser. So if we're talking about just the visible spectrum, since anything outside of that really doesn't matter because we can't see it. Uh, the wavelength we would wind is around five nanometers. That's ideal for brightness and it produces a green laser. So if you're wondering why so many laser pointers were green

for the longest time. It's because that one shows up really, really well with relatively low amounts of power. You don't need to pour a lot of energy in in order to get a nice visible laser beam. But if you wanted other colors, you could get them, but it might require you to pour more energy into it, which means you might need a bigger battery, or it might drain batteries faster. Uh, there are other considerations you have to make so you can make lasers of all different types

of colors. It just requires a lot more energy, and if you pour enough energy in to a laser, it becomes hazardous. Right. A little bit of power can go a long way with certain wavelengths, but with others. If you're pouring a lot of energy in, you can have enough energy there for the laser to do some damage when it comes into contact with something else, like like your hand or your eyeball. So lasers can be particularly

dangerous once you start getting up there in power. I mean they can be dangerous even at low power, but the higher power you go, the more dangerous they can be. And in fact, you can buy lasers at ridiculously powerful levels just online. If you into some of them strong enough to do things like, uh, produce a beam that's concentrated and hot enough to light a match, or pop a balloon, or burn a hole through a thin piece of wood. That kind of thing. It buyer beware, it's

dangerous stuff. But anyway, Disney uses lasers not to burn through the castle because that would be incredibly expensive they'd have to replace it every day, but rather to create embellishments in their show. So if you watch Happily ever After, and there are, by the way, videos online where you can watch the whole show from beginning to end. Disney in fact live stream the very first Happily ever After, and I believe the video from that live stream is

still available online. So you can watch that first one. You'll see the moments where the lasers come in and they will appear to draw on the castle, and the projection mapping, which we'll talk about next, follows along, so that you have what looks like a laser pint brush and it looks like it's actually making the castle change color. Again, that's all part of the projection mapping. It's all timed

out very precisely. So all of these lasers have to be computer controlled, and they're all controlled from their various stations. They're all on gimbals that are motorized so that they can be pointed in the very specific direction they need to be in at the angle they need, and they can all be controlled simultaneously through the computer process. So it's all been programmed so that every single motion is precise and the lasers are all going exactly where they

need to be. Now, that's obviously very challenging for a human being to do. If I were holding a laser pointer, the further away I am from my target, the more dramatic any movement I make is going to be. At the far end of it. Right, you can just imagine if you have a laser that's pointing at a castle that's a hundred and fifty two feet away, tiny little motions on your end are going to be translated into

giant ones across against the castle. Even though it's a small beam of light, you'll see it move in dramatic ways just with tying little motions. So all of this has to be controlled by machine. All has to be automated, and you program it very precisely in a computer. Now, the computer model has to understand and I used to understand loosely here, but it has to understand the dimensions

of the canvas you're painting against. In this case, it would be the Cinderella's Castle at Magic Kingdom and Walt Disney World. And by knowing that, it knows how precisely to move the laser pointer so that it will create the effect specifically where it needs to go, and it can make very smooth and consistent motions. That's the other important thing for any show of this nature, you consistency.

So you want the show tonight to be just as good as the show that was last night, and you want tomorrow's show to be just as good as the last two. So you want to make sure everything is as controlled as it possibly can be, knowing that there are certain elements that are going to be outside of your control, things like weather conditions. That's not something you can really have a say over. So that can that covers the lasers, and there are all sorts of different

colors of lasers that are used in this one. I want to say that there are yellow ones or gold ones that are part of Happily ever after. But there are different colors as well, and those come into various points of the quote unquote story of the show. There's kind of a loose story. It's more like a little vignettes that happened throughout the the experience rather than a

traditional narrative. But that's that technology. Now let's move on to projection mapping, which I'm really excited to talk about because projection mapping is one of those things I just think is super cool. There are tons and tons of videos online showing what projection mapping is, and if you see some of the better ones, the effects are really breathtaking because they're very convincing from the proper angle. But

you have to have conditions just right. You need the lighting to be just right so that the projection you're looking at doesn't get ruined by a lot of ambient light. The more ambient light you have, the more you can see the the object that's behind the projection. The less uh immersive the experience will be, or the less convincing the experience will be. But if you're wondering what projection mapping is, since I haven't really defined it, it is the display of an image on a non flat or

non white surface. So in other words, it's like projecting onto a film screen, only anything could be a film screen. Any three dimensional object could, in theory, be your film screen. The technique has been used for a few years to great effect at various concerts and celebrations. If you've ever seen one in person, you know how dramatic the effects

can be. With the right lighting and projection. As I was mentioning earlier, you can make a building seemed to come alive, or to fall apart, or turn into a giant puzzle. Uh. There are a lot of different videos on YouTube. Just go and look up projection mapping. You're gonna see some incredible stuff. Projection mapping has also been called spatial augmented reality, because you are augmenting reality with

a overlay of information, in this case, projected information. Most of the time we think of augmented reality as some sort of headset we're wearing where we've got display in front of us, and we're looking at a video feed of the world around us, not really the real world. We're looking at it through the camera lens, so we're looking at kind of a monitor, and then we have digital information overlaid on top of that display, and that gives us that augmented reality. This is a differ or

an approach to augmented reality. It is just as legitimate. It is where you are directly projecting onto reality reality itself, so rather than having a screen in front of you, you're looking at the world. It's just that the world also happens to have something projected on top of it that augments the experience, which is kind of cool that it allows you to to make the definition a little

more broad when it comes to augmented reality. It's also been known as video mapping, and Disney, as it turns out, has a really long history with it. Disney has perhaps the first implementation of projection mapping, and that would date all the way back to nineteen sixty nine and a little part called Disneyland, California. Disneyland in nineteen sixty nine opened up a brand new attraction that brand new attractions.

Probably it's definitely in my top three. It is the Haunted Mansion, uh, a ride that is also beloved by Holly Fry here at How Stuff Works. Holly is a huge Disney fan and she loves the Haunted Mansion as well. For a good reason it's a fantastic ride, and the attraction used a lot of different cool lighting and special effects, including the amazing Pepper's Ghost effect, which we've talked about on a previous episode of tech Stuff. In fact, I think I did a full episode of tech Stuff just

on the Haunted Mansion several years ago. But the effect I want to talk about here is one that involves five sculptures, five busts. There are five bust sculptures that are in the graveyard sequence of the Haunted Mansion, and they are of five figures that are singing the song Grim Grinning Ghosts, and um, it's actually the singers. That's their faces that are projected onto these busts. Of the bus themselves are plain white figures that are designed in

the shape of the heads of those singers. But then the singers were shot on film singing along to this song, Grim Grinning Ghosts. That footage is then projected on top of these static sculptures, So the sculptures have no moving parts. Their mouths are not moving, the eyes are not opening and closing, there's no articulation whatsoever. That effect is completely generated by the projection that's on top of the sculptures.

And this was again back in nine, so very forward thinking when it comes down to the effects you would want for your amusement park. Uh. And it's a really early example of projection mapping, perhaps the first one, although I don't have any confirming evidence to say so. Uh. You have to have the projector lined up precisely with the object. It has to be uh calor braided exactly

so that you can get this effect properly. If it weren't done so, then the images of the face would not line up with the actual carved face of the sculpture. Think of it in terms of a movie screen. If you have a movie screen and the projector was off kilter, then the picture you're looking at would not line up

with the screen and things would look strange. You may have even seen this, Maybe you've gone to a film where the projectionist had not corrected for it properly, and the the view of the film was a little too low or a little too high. It's little too low. Then you might see stuff like boom mix that are not actually cut out of the shot. They are just typically out of view because the projectionist lines up the

film in such a way. That you would not see it. Typically, same sort of thing is true with projection mapping, but to a much greater degree. You have to be very precise with how the projection line up with the third three dimensional object that it is hitting. Disney actually received a patent in ninete about projection mapping. The patents title is Apparatus Method for Projection upon a three Dimensional Object,

which again was pretty much projection mapping. And from that patent is the following statement, which really sums up the challenges that you face if you want to create this effect. The projection of an image onto a three dimensional object having various contours and shapes is not an easy task. It is generally known that the correction of all optical distortion problems inherent in flat two dimensional image projection is

especially difficult when working with three dimensional projection surfaces. These problems include proper image registration on the object, proper keystoning corrections to ensure appropriate perspective appearances, and focusing of the image within a specified range of depth. So what that's saying is, when you've got a distorted screen, which is essentially what a three dimensional object would be, you can't just easily map a two dimensional image on top of it.

It's It's kind of like if you grabbed a paper map and try to lay it down on top of a globe. While the paper map has been designed in such a way to mimic the Earth, but obviously lots of different considerations had to be taken into effect to make that happen. When you are trying to convert a three dimensional object into a two dimensional rendering, you have to make some sacrifices. You can't just slap the map

back onto a globe and have it look perfect. It's not going to You have to You would have to warp things within the image in order to have it line up properly so that it would look the way it should on a globe. The same thing is true with projection mapping. You actually have to warp the image so that when it's overlaid on top of the three

dimensional object, you get the effect. Do you one. Now I'm gonna talk a lot more about projection mapping, but first let's take another quick break to thank our sponsor. Let's talk a little bit about the concept of spatial augmented reality. I mentioned I mentioned earlier that's sort of the academic name for what is projection mapping. This became an area of study really in the late nineteen nineties.

So even though Disney had pioneered some of this work in the late nineteen sixties, it wasn't until the nineteen nineties that a lot of work was being done on it, because, again, to do it on a big scale was really tricky unless you started taking a computer science approach, and that's exactly what was going on in the nineties. That was largely the domain of a group of researchers who are

working at the University of North Carolina Chapel Hill. They wrote a paper called the Office of the Future, and in that paper they imagined an office that would have lots of projectors everywhere, and the projectors would allow you

to turn work spaces into all sorts of different augmented experiences. So, for example, let's say that you're working on a collaborative project, you might use all these different projectors to allow you to work uh interactively in an environment that would let you visualize exactly what you're talking about, even if what you normally would use just spreadsheets. So it's kind of a cool idea, but very heavily relied upon this idea

of projection mapping. One of the people working on that was Ramesh Rascar is one of that University of North Carolina group, and he also worked on a tech that he called shader lamps. Shader lamps would allow you, through projection to create different effects on stationary three dimensional objects, as if you were using a digital canvas. So you might think of shaders on graphics, you know, Shaders are things that allow you to work with light in different ways.

That was the purpose of shader lamps to create light in specific ways to protect against three dimensional objects and then create the different effects that you want. And there's actually a really cool video that I watched where he walked through this process and he showed a neutral colored vause. The vase was sort of an off white color, is just plain, no texture, no pattern on it, and projected different images onto it so that it had a pattern

or it appeared to have texture. The one that I really liked was one where it was a very convincing illusion that there was a patterned vase rotating perhaps on like a lazy Susan, But it turned out the vase was completely stationary. It was not rotating at all, it was just a solid color vase. It was the image that was making it look like it was rotating. It's the same basic principle that we have for film. We're watching a series of images that, when they are played

back at a certain frequency, appear to simulate movement. Same thing is true with projection mapping, but it required that you have this approach where you are conforming the image projected to the object shape and size. So it's a little more tricky. It's not just well, let's move the projector a little bit closer to the screen or a little further away from the screen because the image that's being shown is too big or too small. It also involves the actual contours of the device you're or the

the object you're using. And he pointed out the two main problems of projection mapping are aligning each individual projector so that the images they display line up with the physical features of the three dimensional object itself. So, for example, corners or in the case of Cinderella's Castle at Disney, you've got the different parapets, you've got the different doors

and windows. All of that has to line up icily with the the projection or else you're gonna have this weird overlay effect where the image is not quite on top of the physical part of the castle it's supposed to be laid against. So that's one of the two challenges.

The other big one is you typically need more than one projector because you have to hit an object at various angles, and if you have one projector, all that light is just coming from one side, and if you're at any other viewing point around this three dimensional object, you're not going to get the effect of the projection. So you have to have multiple projectors all aiming at

the same physical object. They each have to be calibrated properly with that object, with respect to the object and with respect to each other, so that the seams of those images line up precisely. If you have a character, and animated character show up on one side of the castle and then make his or her way around to the other side of the castle, and in that journey that character gets handed off from one projector to another, obviously you need to have that lineup as as best

as possible to have a seamless experience. You can cheat a little bit with an object like Cinderella's castle, because you could have the character go into or appear to go into a tower or a window or a door, and it's kind of like a cut in a film. You could then have the character emerge from another window or another door, and it's being handled by a totally different projector, and because you had the character move out of sight for a moment, you don't have to have

that truly seamless experience. You don't have to have those two projectors synchronized so precisely that there's no overlap, where otherwise you might end up with quasi Modo having four arms, which would make him even less quasi modo, or more quasi and less modo whatever. Hunchback of Notre Dame is a terrible Disney movie. Come at me, so very difficult problems to solve, and typically you have to design computer software in order for you to be able to do this. Uh,

you being the person trying to create projection mapping. Luckily for us, if we were interested in doing our own projection mapping project, there are lots of software packages out there that are designed to do this, and typically the way it works is you would download one of these software packages, which tend to cost and a few hundreds of dollars, somewhere between three hundred and eight hundred dollars

truly is not that much. When you look at video software, there's a lot of video editing software that's in that range. So something that's on this scale, which is meant to project against large objects, it's not really that outrageous to have a piece of software cost a few hundred dollars.

You pair it with a projector or multiple projectors, and you typically would set up an object where it would be in the pathway of the projector, and you would use the software to manipulate a field on top of virtual field on top of the actual object, and what would happen is the projector would project an image, it may be a grid, for example, to define the areas of that object, and you would use the software to conform the grid so that it met the parameters of

that object. So you are mapping the object itself within the software. You're defining the areas that you can paint against your defining the screen itself. And it's kind of like using photo editing software, except instead of just cropping a photo, what you're doing is you're just defining the

edges of your image. So if you're doing something like Cinderella's Castle, you would say, all right, I want this tower, and I want the parapet at the top of the tower, but I don't want any of the edges to fall into this because we won't be able to see it. The projection will go just past the edge of the tower and there's nothing for the image to be projected against at that point, So we want to make sure

that we define those edges within the software. Once you've done that, then you can start to animate or design lighting effects against that now virtually defined space. You also have to keep in mind that the distance between the projector and the object has to be established so that the scale remains the same. If you were to bring the projector closer or further away without adjusting lens, that's

going to affect both the focus and the scale. So there are a lot of different elements that are at play with this technology, and if you want to work just right, you have to find the right place to set up your your technology. You have to calibrate it precisely, and then you have to make sure that nothing moves so that it's all lined up and stays lined up. So in this display or this this demonstration I was

talking about earlier. They show that they'd use a program to define specific points on the three dimensional surface from the point of view of the projector in order to calibrate the system. So you would just use essentially a mouse moving a cursor to different points on the image

of this three dimensional object. So you've got a camera and a projector that are lined up with each other, and you use the mouse to define, all right, this is an edge, this is an edge, or or here's a point, here's a point, here's a point, in order to calibrate it with the projector itself, and using multiple points allows for the system to line up precisely with the object. If you just clicked one point, there's not

enough reference there. The image coordinates for the projectors are in two dimensions, you know, X and y axis, because depth is not really something a projector handles. A projector can't make the light stop at a certain distance. It's going to keep going till it reflects off of something. So you just are concerned with X and y and then you warp that depending upon the actual depth of the physical object you're shooting against or you're projecting against

the actual points in space. Therefore are three dimensional, even though the data inside the projector is two dimensional, because those points in space have to conform with the physical features of a real object. In the demonstration I watched, they were projecting images on a model of the taj Mahal and it was very effective. The system, according to them, required about five minutes to calibrate per shader lamp, so that's not very long. I have no idea how long

it takes to calibrate the Disney system. I was not able to chat with anybody to get that information, but I imagine it's again very precise and probably takes a few minutes to make sure that it's lined up reliably. Once set, then you just you said it. You leave it, you walk away, you don't touch it. Now, you can't just grab any old projector and a white or other

neutral colored object and just go to town. The images you project will not match up with the object you're projecting on, so you have to have that way to warp the image so it lines up. I talked about this a second ago. You use that software to conform to the three dimensional object, um you needed. You need

a computer obviously to run the software. The computer needs to have a pretty powerful processor and a really powerful graphics processing unit or GPU, because you need the processor that's strong so it can send a lot of data to the GPU consistently. You need to have a good pathway between processor and GPU, so that you also need

a really good bus between the two. The GPU needs to be beefy because it's going to be sending a lot of data to the projector, and the more um high res the inag, the more data it has to send. If you're doing something on the scale of what Disney wants, chances are you've got pretty high standards for the resolution.

Even keeping in mind that you're projecting this against an enormous castle and most people will be dozens of feet away, you still want it to be a really crisp image, So you're going to need some pretty powerful machines with really strong processing abilities to carry this off and send that information to your high res projectors to shoot it

against the three dimensional object in question. Keeping in mind you're probably using multiple projectors, so that reduces the need for the the landscape you're covering for each projector, and thus, if each projector is lined up with a different dedicated computer. You can divide up the job a little bit, although all of those computers at some point have to be coordinated with one another. Otherwise you would have different parts of the show showing up at different segments and it

would just be a mess, a chaotic mess. Projectors have something called a throw distance, that is the distance between the projector and a screen that it can show an effective image. So that's something you have to take into effect. Uh, you also have to worry about making sure that you've got the right you know, all the resolutions are the are the same, because otherwise, if the resolution of one projector is different from another, you're gonna have a very

muddy effect on the three dimensional object in question. As I said, there are a lot of different software packages out there. There are some free ones if you want to try some projection mapping, although there reliability maybe a little less resilient than what you would get with a paid software package, But there are some out there that

you can look at. But there there's tons of different projection mapping software suites out there if you if you're really serious of about doing this, you can PLoP down some cash and you'll get a more reliable and possibly more user friendly set of tools to do this yourself.

To develop the Disney show, they started with a scale model of the castle, so everything had to be precisely at the right dimensions with one another in order for them to use that as their working model, because obviously they couldn't do this every single day out of the park there are people there, so to develop it, they needed to make a perfect scale model of Cinderella's Castle

and use that to plot out their show. And they did this everything from the full narrative arc like what's the story they're trying to tell, to the particular animations and effects that they were trying to create. Obviously, anything that involved pyrotechnics probably they didn't throw in there, because shooting fireworks off inside is never a good idea. But for all the three D projection mapping techniques they could use.

Those they could actually set up projectors and projected against the three dimensional scale model they had and see what it was going to look like on the small scale before they built up and worked on it for the actual park. They called in as many of the original animators for the various films that they reference in the show, so throughout the show, different iconic characters from Disney movies

show up on Cinderella's castle. Uh, for example, Merida from Brave or Aladdin from Aladdin, We'll show up and they'll interact with the castle in some way. They tried to get as many of the original animators back to work on those characters as they possibly could, So it's a big thrill for a lot of those folks because they hadn't had a chance to work on those characters in

some cases for several decades. And uh, it really is nice to be able to see those characters come to life and have the same sort of qualities that they had in the movies that they became famous for. So that's kind of cool thing too, is not just the technology, but if you are a Disney fan and you're also a fan of the process of animation, knowing that it was the same people responsible for bringing that to life the first time is really something special because it's it's

you know, it's it's calling back to a nostalgic time. Now, of course, that wasn't the case for every single piece of animation they referenced. In some cases, those animators have passed away, especially for the really old classic Disney animated features, but it was a pretty impressive spectrum of characters, everything from the more recent shows and films, things like Mowanna and Zootopia too, classics like Sleeping Beauty. Well, we will

never get rid of Maleficent. I think she's always going to be a villain in every single Disney nighttime spectacular because how can you how can you leave out a an evil fairy queen who assumes the shape of a dragon. That's that's pretty awesome, but I think that's a particularly

interesting part of Happily ever After. Artists when they were working on this, we're working on digital services, so think of like, uh, an interactive screen, not not necessarily a tablet, but a display that they could directly draw on using light pens or digital pins. So they had the representation of the castle there, which was essentially a visual interpretation of the virtual model that they had created. So they had created a virtual model by defining the aspects of

that castle the way I mentioned earlier. Artists could then draw against that and create the effects directly in the software, which then could be projected against the castle when they wanted to test things out, And this allowed them to developed the show relatively quickly. It still took a very long time, but it allowed for very quick prototyping and testing of different effects and transitions and sequences, which is pretty cool. And at the end of the show spoiler alert,

tinker Bell comes out and flies over the crowd. This is something that's been going on for decades over at Disney and I think people would have rioted if tinker Bell had been removed from the experience, so uh. At Disney World, tinker Bell has been part of the nightly show since July third n at the Magic Kingdom. She hasn't appeared every single night because her appearance is dependent upon the weather. If the weather is if it's too windy or stormy, then tinker Bell will not be coming out.

Because Okay, for those of you who don't want the magic ruined, you should probably stop listening right now, so I'm gonna give you a second. For the rest of you, Ramsey just took off his headphones. Jokes on him. He's like three ft away. He has to listen anyway. Tinker Bell is an actress, right all right. I hate to say it because I don't want to ruin the magic, but she's an actress typically sometimes an actor, but typically an actress and tinker Bell um. You know, they have

to keep tinker Bell safe. So to that end, if the weather conditions are unfavorable, tinker Bell does not fly. Tinker Bell's flight is along a zip line. There is a zip line that is approximately eight hundred fifty feet long. It extends from the Cinderella's Castle from one of the towers, and it ends on the top of tomorrow Land Terrace d fifty feet away. A flight down tinker Bell's zip line takes about thirty seconds. So let's do some math here.

Eight hundred fifty feet and thirty seconds translates to about nineteen miles per hour. That actress is zipping down a zip line at nineteen miles per hour in a tinker Bell costume that lights up, has led lights, there's a battery pack and everything. Uh, this means that tinker Bell has to meet some certain certain criteria. There's certain rules that you have to follow if you wish to be tinker Bell, and they're a little precise. I was going to use the words draconian, but that might be a

little too cruel. So, for example, to be tinker Bell, you must be no taller than five ft that is the maximum height for tinker Bell. That's partly so that you get the wonderful illusion of the fairy flying over the audience. And you must weigh no more than one hundred five pounds because you're in a harness on a zip line, and that harness is rated up to a certain weight, which is well over a hundred five pounds.

Clearly you wouldn't rate it at the in the cap weight, but that's why one of the reasons why I'm sure they have this strict weight limit of a hundred five pounds. Tinker Bell sometimes is played by a guy. Occasionally there's a fellow who will have to step in as tinker Bell if the actress typically playing tinker Bell is unavailable for whatever reason. At the end of the flight, you are greeted if you are tinker Bell, to the warm embrace of a net being held by a couple of

technicians or cast members. Everyone who works at Disney is a cast member, so the net will slow you down, and you end your last little bit of your journey against a gymnastic matt that's on its side, so it's up against the edge of the or wall. Of the tomorrow Land terraces, so that way, if the net doesn't slow you down enough, you don't just go crashing into a wall. Um all right, So I'm done ruining the magic. That's it. So that's kind of the lowdown on Disney's

Happily ever After. It is a great show if you have not seen it. There are videos on YouTube you can watch Happily ever After, and it's about an eighteen minute long display, so it's it's a doozy um. The technology is really impressive. I will say that I've watched the videos, it is way more impressive to see in person. So if you're already going to the Magic Kingdom, and if Happily ever After is scheduled to happen the night you are there, I highly recommend checking it out. I mean,

you could go and ride more rides. There are gonna be a whole lot of people watching the show rather than doing that. But if you if you like Disney films in particular, and you really like fireworks, displays and uh, you know, innovative technology, I highly recommend it. It It is is a really well done show. It's not as narratively cohesive as I typically like. I like stories that have more to them than that. But it is a lot of fun to watch the different vignettes, and there's certain

segments that just find breathtaking. I love Meredis segment. In that section, the entire castle appears to be covered in ivy and it's just really vibrant. And I also love Molana's section. And uh, there's a little bit at the end with with Simba's dad and with the song go the Distance from Hercules. This is particularly moving. Got dusty and ear. Okay, that's enough of that. I'm glad I had a chance to actually talk about this because again I had been planning it since before I took my trip.

And uh, while I didn't get a chance to talk to any imagineers, and I hope one day to correct that. I would love to chat with some imagineers about what they do, because I think it's incredible the work that goes into creating these different Disney attractions. It's it's phenomenal stuff. I am very thankful that Disney was kind enough to extend to me a a pass for the day. Um I stayed for more than a day, so I bought all the other days, but one of those days was free.

So just full disclosure again you guys. That wraps up this episode of tech Stuff. If you have suggestions for topics I should cover in future episodes, whether it's a specific technology, a company, a person in tech, let me know. Maybe there's someone you want me to interview, Maybe there's someone you want as the perfect guest co host. Send me a message. You can email me. The address is text stuff at how stuff works dot com, or drop

me a line on Facebook or Twitter. The handle it both of those is text stuff h s W. Remember I live stream shows on Wednesdays and Fridays. You can go to twitch dot tv slash tech stuff and there you'll find the schedule. You can pop in join the chat room and I will be happy to chat with you between segments and just see what's going on in your world. And that's it. I'll tak you again. Release it for more on this and thousands of other topics, is it how stuff works dot com